Gas discharge overvoltage arrester

Abstract

An overvoltage arrester for high surge currents having an increased useful life while maintaining suitable electrical properties comprising a pair of electrodes secured to an insulator housing in confronting, spaced relation to provide a discharge gap, the electrodes being covered with a metallic activation compound comprising metallic barium aluminum dispersed in a matrix of metallic aluminum, the matrix being fused onto the confronting surfaces. Additional metal additives may be embedded or alloyed with the metals of the activation layer.

We claim as our invention 
     
       1. A gas discharge overvoltage arrester comprising: an insulator housing,   a pair of electrodes secured to said housing in confronting spaced relation to provide a discharge gap therebetween, and   an activation compound on the confronting surfaces of said electrodes, said activaton compound comprising particles of an alloy of barium and aluminum uniformly dispersed in a matrix of metallic aluminum, said matrix being fused onto said confronting surfaces, the metallic aluminum constituting 10 to 40 weight percent of said activation compound.   
     
     
       2. An arrester according to claim 1 wherein said activation compound also contains at least one additional metal selected from the group consisting of Ni, Mo, Cu, Ag, Cr, and Zr, said additional metal being present in an amount of up to 40% by weight of said activation compound. 
     
     
       3. A method for the manufacture of a gas discharge overvoltage arrester which comprises: combining powdered metallic aluminum with a powdered alloy of barium and aluminum to form a mixture,   applying said mixture to a pair of electrodes,   inserting said electrodes into an insulator housing, and   soldering said electrodes in spaced relation to said housing at a temperature of from 700° to 900° C.